Dude, Where’s my Bandwidth?


by Adam White | 07.05.2012
Categories: Blog

Your organization may have an internet connection or a WAN connection rated at say 5, 10, or even 100Mbps. That’s ONE HUNDRED MILLION ones and zeros every second! So why does it feel more like you’re cruising around in a Chevette than a Corvette sometimes? The reason could be related to a variety of factors. Let’s look at a few of the more common ones.

# of Users

This one is pretty obvious. A 10Mbps connection may be just fine for 50 users…but 500 users? You can divide your satisfaction level by about ten. The more users (and devices) you have on your network, the more data will be traveling in and out of it. Emergent Networks can setup some simple monitoring to establish a baseline of how much bandwidth your organization actually uses.

Video/Audio & Non-Business Applications

Five hundred Outlook users won’t use nearly as much bandwidth as 50 YouTubers.  Video & audio consumes A LOT of bandwidth.  Making users aware of the types of applications that consume resources can help.  Emergent can also help you put an enforcement mechanism in place that will identify and police non-business related traffic that your business apps may be competing with for space in the pipe.

Using technologies like SNMP & NetFlow we can help you identify how much traffic is being sent and received, what the traffic is, and who is doing the sending and receiving.  These reports can be useful for educating users.

Duplex/Speed mismatch

It seems like every few months that I run into a connection that just isn’t working the way it’s expected to.  After a little troubleshooting it becomes apparent that a WAN or internet connection has a lot of errors caused by a duplex or speed mismatch.  These are basic settings that routers and switches must agree on like, “Can I talk and listen at the same time?  Or should I wait for you to be finished before I try to talk?”  Check out the effect of a duplex mismatch on the throughput of this 20Mbps link!

20Mb circuit WITH a duplex mismatch…ouch

After resolving the mismatch…that’s better.                              

It’s always a good idea to scan your network for half-duplex links and investigate each of them.

Upstream Issues

ISPs and WAN Service Providers have networks just like yours.  That is, they have issues from time to time.  Few things are more frustrating than being caught in between two vendors blaming each other for a problem.  With Emergent as a partner you’ll have someone to work with your WAN or Internet Service Provider to find the root cause of slow bandwidth.


A 100Mbps internet circuit at your HQ is great…for your HQ users that is.  But if you have users in a branch that are connected to your HQ via a T1 then they’re only ever going to have access to a tiny fraction of that.  Having a solid understanding and clear documentation of you network is key to understanding performance on your network

Try This

Perform your own speed test at or contact Emergent Networks to conduct some more thorough testing of your WAN/LAN.